In biological research, drug development research, and other areas of clinical, evolutionary, and basic research in microbiology and cellular biology, there remains a need for methods and compositions suitable for the characterization of cells, including but not limited to microbial cells, animal cells, and plant cells. Indeed, methods and compositions are needed for the characterization of cellular properties that may or may not change, depending upon genetic changes and changes in the intracellular and extracellular environment, including exposure of cells to biologically active chemicals.
In addition to the need for identification and characterization methods for microorganisms and other cells, there remains a need for pharmaceuticals for treatment of infectious, as well as non-infectious disease. Indeed, there is a need for methods and compositions to assess cellular phenotypes and the reaction of cells to the environment. Typically, the process of developing pharmaceuticals involves the steps of defining drug targets and testing potentially active chemicals to find the ones that specifically interact with the target to produce the desired effect without undesirable side effects. Although much work has been done in this area, there remains a need for improvements in the efficiency and effectiveness of the testing and evaluation of these chemicals.
In response to the pressures to generate more promising drug candidates, pharmaceutical and biotechnology companies have turned toward rapid, high-throughput methods to find and evaluate lead compounds. These lead compounds are typically selected by testing large libraries of compounds compiled from a wide variety of sources, using collections of extracts, chemicals synthesized by combinatorial chemistry approaches, or through rational drug design.
However, these methods have been a mixed blessing. Technologies such as combinatorial chemistry allow for rapid generation and testing (e.g., screening) of libraries of compounds against potential drug targets. Unfortunately, these technologies only look at the effect of the drugs on the proposed target, and they do not measure the effect on other cellular processes. A chemical may be an excellent candidate based on its interaction with the target protein, but it may also interact with other proteins in the cell and cause side effects. Thus, a major problem remains, in that the drug developer must sort through promising drug candidates to see how they effect other aspects of cell function, as well as how the drug candidates interact with other drugs that may be used simultaneously. Despite advances in these fields, there remains a need for highly sensitive and specific, yet cost-effective and easy-to-use methods for the identification and development of compounds (e.g., biologically active compounds) that are effective in the treatment of infectious and non-infectious diseases.